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A low power and low noise infrasound sensor for temporary measurements. Damien PONCEAU, CEA/DIF/DASE Sébastien PEYRAUD, CEA/DIF/DASE Patrick DUPONT, CEA/DIF/DASE Stéphane DENIS, CEA/DIF/DASE 2008 ITW, Bermuda, 03/11/2008 damien.ponceau@cea.fr , stephane.denis@cea.fr , www-dase.cea.fr.
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A low power and low noise infrasound sensor for temporary measurements Damien PONCEAU, CEA/DIF/DASE Sébastien PEYRAUD, CEA/DIF/DASE Patrick DUPONT, CEA/DIF/DASE Stéphane DENIS, CEA/DIF/DASE 2008 ITW, Bermuda, 03/11/2008 damien.ponceau@cea.fr , stephane.denis@cea.fr, www-dase.cea.fr
Presentation layout • Temporary measurements : • Examples • Requirements • IS Sensors and measuring chains : • State of the art • Comparison vs temporary measurement requirements • MB2007 microbarometer : • Principle • Lumped elements model: • acoustic impedance, response, noise and range • MB2007 calibration • Early field results
IMS network, DASE measurement sites • For each site: • Volume:~ 30 L • Weight: ~ 20 kg • Power consumption:~ 7 W • Dynamic range: > 108 dB • Resistant equipment IS stations installed by DASE http://www.rdss.info/ Pipes, meteo. and telecommunications not included
Some temporary measurements in IMS framework J. Guilbert, P. Harjadi, M. Purbawinata, S. Jammes, A. Le Pichon, B. Feignier, « Monitoring of Indonesian volcanoes with infrasound : preliminary results, SURvey of Volcanic Arc of Indonesia », Infrasound Technology Workshop 2005, PAPEETE. • Le Pichon, K. Antier, S. Vergniolle, M. Lardy, D. Drob, « Validating upper-wind models using infrasound from active volcanoes in Vanuatu », Infrasound Technology Workshop 2006, FAIRBANKS. A. Smirnov, V. Kunakov, A. Le Pichon, J. Guilbert, D. Ponceau « Preliminary results of localization and characterization of steady infrasound source as detected by I31KZ », Infrasound Technology Workshop 2007, TOKYO.
IMS IS Temporary measurements requirements • Some IMS requirements1: • Able to solve IS Low Noise Model @ 1 Hz. • Dynamic range > 108 dB. • Additional requirements2: • Portable, easy to transport and install. • Plug and play. • Resistant equipment • unsensitive to changes of geographical and meteorological conditions. 1Working Group B, CTBTO Preparatory Commission, « Operational manual for infrasound monitoring and the international exchange of infrasound data », Rev. 10, 7 Sep 2004. 2O. Sow, CTBTO Preparatory Commission, « Terms of reference, procurement of infrasound experimental array », CTBTO Preparatory Commission Request for proposal, ref. no. 2007-0213/SOW, 22 Aug 2007.
New “24 bits” acquisition systems • Common features1: • Portable & plug and play: • Power input range : ~ [9, 30] V • Volume : < 5 L • Weight : < 5 kg • Power consumption : < 1.5 W • Dynamic range (with symmetric input) > 120 dB • Resistant equipment • And others 1 A. Brisbourne, A. Paul, M. Alvarez, R. Sleeman, « State of the art digitizers », ORFEUS NERIES joint workshop, October 2007.
MB 2005 : Current solution vs requirements • Portable & plug and play: • Power input range: ~ [9; 30] V • Volume & Weight: < 20 L, < 15 kg • Power consumption: < 3 W (up to 2 W) • Dynamic range: > 108 dB (sensor) > 120 dB (digitizer) • Resistant equipment Pipes, meteo. and telecommunications not included 2 days batteries included. ~ 450 x 300 x 200 mm3
MB2007 microbarometer : objectives • A new Absolute pressure sensor : MB2007 • Low power • Integrated calibration • Optimize the use of digitizer dynamic range • Portable • Reliable • To better fit the low noise model at low frequencies
Aneroid capsule impedance, Zaan Bellows and reference cavity spring rates are predominant over infrasound frequency band First batch of prototypes: Zedr >> Zece Modelled as a capacitance over infrasound frequency band MB2007 microbarometer: acoustic impedance
MB2007 microbarometer calibration, 10 Pa sinus Aan, aneroid capsule effective area BLm, velocity transducer generator constant Kan, aneroid capsule spring rate Uo, output voltage pe, input pressure Considering previous simplifications: 1 2 3 4 MB2007& IS Calibrator
Amplifier voltage noise Coil resistance thermal noise MB2007: noise measurements @ LOR
MB2007 pressure range Mechanics Digitizer
MB2007 specifications MB2007 & MB2005
Conclusion : near future measuring chain • Portable & plug and play: • Power input range: ~ [9; 36] V • Volume & Weight: 5 L, 9 kg • Power consumption: < 800 mW (up to 300 mW) • Dynamic range: > 130 dB (sensor) > 120 dB (digitizer) • Resistant equipment
Conclusions & Outlooks • Temporary infrasound measurements imply new requirements for equipments. • Thanks to recent developments in digitizers and infrasound sensors, more appropriate solutions become available. • MB2007 outlooks: • Models and uncertainties on each parameters to improve • Susceptibility to harsh environments to study • Susceptibility to aging to study • To measure signals, collocated with other sensors